The Interrupted Journey

The Interrupted Journey is a 1949 British thriller film directed by Daniel Birt and starring Valerie Hobson, Richard Todd, Christine Norden and Tom Walls. In the film, a man fleeing with his mistress narrowly escapes a train crash after he pulls the emergency cord and is wracked with guilt. The railways scenes were shot at Longmoor in Hampshire.

As they are embracing the sound of a massive train crash reaches the house. Carol immediately runs to help the victims, while John stands there stunned as he realizes it is the train he has just left that has been involved in the disaster. After they run down to help North walks amidst the chaos and from a shattered carriage he catches sight of a lifeless arm sticking out of the wreckage that clearly belongs to his lover Susan Wilding. She and everybody else in the carriage has been killed in the collision. North chooses to say nothing about his presence on the train to his wife, maintaining that he returned from London by road.Over the next few days North is guiltridden as the details of the crash emerge. After the train stopped when he pulled the cord, it was struck by a goods train. There are dozens dead and injured and bodies are still being dug out from the wreckage. Norths problems increase with the appearance of Clayton, an idiosyncratic British Railways crash inspector, who begins to ask questions that clearly unnerve North. North denies any connection with anyone on the train, although Clayton has recovered documents connecting North and his mistress which were found on the man who had been following them, a private detective hired by her husband, who had also died in the crash. ........

Source: Wikipedia